practice exam questions

Question 1

On T1-weighted MRI images, tumors can be better recognized by using the MRI contrast agent
Gadolineum. What are the underlying mechanisms for high uptake of Gadolineum by the tumor, and
why is the tumor signal intensity higher on these MRI images. (3 points)

Answer 1

There is high uptake of gadolinium by the tumor because of leaky vessels and more perfusion. The signal intensity is higher because gadolinium shortens T1.

Question 2

Mention and explain two features of MRI imaging, which are the reasons why MRI-guided radiotherapy is better than CT-guided radiotherapy. (4 points)

Answer 2

MRI is able to give soft-tissue contrast, to see the difference between healthy tissue and affected tissue. CT is not able to do this.
MRI is able to image moving organs in real time, whereas CT cannot.

Question 3

Mention and explain three measures which can be taken to minimize the amount of radiation, to which the patient is exposed to for plain radiography. (3 points)

Answer 3

Limiting the radiation to only the area that needs to be imaged
Only image what is minimally required, reduce exposure time and number of images.
Placing the radiation source under the table, then absorption by the table will be first before the radiation gets to the patient.

Question 4

Diffusion-weighted (DW) MRI is a tool to diagnose cancer. Is the DW-MRI signal intensity in tumors
increased or decreased, as compared with healthy tissues (1 point). Explain your answer (2 points).

Answer 4

Increased, because there is less diffusion in the tumor due to increased cellularity. Because of this, the diffusion-weighted gradients have less effect of lowering the MRI signal intensity.

Question 5

A new anti-cancer drug has been developed, but it is still to be determined if this drug reaches the
tumor in the patient’s body. Describe in three steps how this question can be answered by nuclear
medicine imaging. (3 points)

Answer 5

1. This drug could be coupled to a radioactive nucleus to make a radioactive tracer, 2. the tracer gets injected into the patient, 3. we can observe via PET-MRI if it reaches the tumor location and what the biodistribution of the drug is..

Question 6

Describe which imaging techniques can be used in oncology for staging and restaging of prostate
cancer. (2 points)

Answer 6

PET- MRI and PET-CT

Question 7

Which radiotracer is generally used in oncology (1 point). Which radiotracer is specific for prostate
cancer? (1 point)

Answer 7

18-F FluoroDesoxyGlucose, 68-Gallium labelled Prostate Specific Membrane Antigen

Question 8

The apparent diffusion coefficient (ADC) is a value that describes the overall diffusion of water. In healthy adult brain tissue, the ADC values of white matter and gray matter are similar. Give an example of the most common pathology in which ADC is strongly reduced (1 point) and describe the changes in the tissue that cause this effect. (2 points)

Answer 8

Stroke, because of hypoxic ischaemia there is a smaller extracellular space that the water molecules can travel in, causing restricted diffusion as compared to healthy tissue.

Question 9

Usually the half-life of the radio-active nucleus in tracers is in the range between 1 to 12 hours. But in
making a tracer for monoclonal antibodies, the radioactive nucleus 89-Zr is selected with half-life of 78 hours. Why is this longer half-life needed? (2 points)

Answer 9

Because monoclonal antibodies need 2 days to arrive at their target due to a slow metabolic pathway.

Question 10

A patient with acute lymphoblastic leukemia relapses and is resistant to all chemotherapeutic
treatments. He is a candidate for adoptive cell therapy. The patient’s lymphocytes were too weak and could not be isolated. The doctors decided to treat the patient with allogeneic T cells. What are the three requirements the allogeneic T cells should fulfil in order to be efficient and safe? (3 points)

Answer 10

Tumor specificity through a receptor (TCR or CAR),

Cells should not express a possibly alloreactive endogenous TCR (prevention GvHD),

Knockout HLA gene expression (To prevent T cel and NK cell immune rejection of injected cells)

Question 11

Explain the molecular structure of a Chimeric Antigen Receptor (CAR) naming four of its domains
present in first-generation CARs. (4 points).

Answer 11

Antigen binding domain derived from an antibody,

Short hinge for flexibility,

Transmembrane domain derived
from CD8/CD28

Stimulatory domain from CD3z.

Question 12

Name two commonly used diagnostic laboratory techniques used to identify different types of
leukemia. (2 points)

Answer 12

Morphology determination by microscopy, multiparameter flow cytometry.

Question 13

Cancer immunotherapy has not yet proven successful in glioblastoma patients. Give two reason why.
(2 points)

Answer 13

Because the tumor has a low mutational rate, meaning there are hardly any neoantigens, and suppression of T cells.

Question 14

A good WHO or ECOG performance status is a prognostic factor for metastatic melanoma patients
treated with a checkpoint inhibitor. Give three additional factors that are known to influence prognosis for metastatic melanoma patients on checkpoint inhibitors. (3 points)

Answer 14

Mutational load, Symptomatic brain metastases, Stage of disease.

Question 15

Oncolytic viruses selectively replicate in tumor cells, leading to their lysis.
Immunity plays an important role in the therapeutic effects of oncolytic viruses. Please explain how
oncolytic viruses enhance antitumor T cell immunity. (5 points)

Answer 15

Induction of immunogenic death, leads to

the combining of Ag release and DAMP-mediated APC activation, which leads to

antitumor T cell priming which leads to
APC activation with chemokine release which leads to

T cell recruitment and turning tumors ‘hot’

Question 16

Provide two reasons why it is important to determine the immunoscore in the tumor microenvironment, discuss numbers and location. (2 points)

Answer 16

To determine the number of effector cells and to determine the location of the immune cells, if they’re in the core of the tumor or around it (hot/cold tumors)

Question 17

Vaccination strategies that specifically target dendritic cells (DCs) are being developed for anti-tumor
immunotherapy. What is the purpose of specific DC targeting and how can we realize this targeting to e.g. C-type lectin receptors? (2 points)

Answer 17

The purpose of specific DC targeting is to lead to DCs starting to form an anti-tumor response.
We can realise this by addition of the natural ligand or antibodies.

Question 18

Besides inclusion of the tumor antigen, what is another important component of vaccines targeting
dendritic cells (DCs). (1 point)
On which two processes can this component have an effect at the level of a DC? (2 points)

Answer 18

An adjuvant ligand. The two processes that this has effect on is the co-stimulation and cross-presentation.

Question 19

Which two classes of therapeutic anti-cancer monoclonal antibodies can be distinguished based on
fundamental differences in their mechanisms of action? (2 points)

Answer 19

Checkpoint inhibitors and against tumor antigens.

Question 20

A female patient is diagnosed with HPV-induced oropharyngeal cancer. She is treated by
chemoradiotherapy. She asks you as treating physician whether she is still infectious for her partner
and children during the time that the tumor is being treated. What should be the correct answer to her? (1 point)

Answer 20

No, when the virus caused cancer it loses the ability to produce virions and infect other people.

Question 21

The current diagnostic procedure for prostate cancer is highly invasive. Give two more reasons why
non-invasive biomarkers are urgently needed for prostate cancer. (2 points).

Answer 21

Risk estimation is inaccurate and biopsies can miss the tumor whilst it is present.

Question 22

Name three risk factors for developing pancreatic cancer. (3 points)

Answer 22

Smoking, drinking, obesity.

Question 23

A patient with non small cell lung cancer (NSCLC) is diagnosed with advanced stage of the disease
where the cancer has metastasized to distant sites, among which the brain. Different 1st line treatment modalities could be considered for this patient. What stage of the disease does this patient have? (1
point)

Answer 23

4

Question 24

Provide two reasons that will exclude this patient from being treated with immunotherapy with
checkpoint inhibitors (alone or combined with chemotherapy) as a first line treatment. (2 points)

Answer 24

Active infection, oncogenic drivers, auto-immune diseases, Ecog 2-5